In order to prevent a lateral rollover of a vehicle, a technique for reporting the danger of lateral rollover has been proposed (refer to, for example, Patent Documents 1 and 2).
With the invention disclosed in Patent Document 1, on a two-dimensional map in which the roll angle and the roll angular velocity of a vehicle are used as parameters, a lateral rollover limit curve is set, with a region in which the roll angle and the roll angular velocity are greater being set as a vehicle lateral rollover region, and when the history of the roll angular velocity which has been detected with a roll angular velocity sensor 1 and the roll angle exceeds the lateral rollover limit curve, entering the vehicle lateral rollover region, it is determined that there is the possibility of the vehicle being rolled over. In addition, with the invention disclosed in Patent Document 2, when the angle formed by the line connecting between the center-of-gravity location of the entire working machine and the overturning fulcrum and the vertical line (the repose angle) is greater than the limit repose angle, it is determined that the vehicle body is in a safe posture, while, when the repose angle is under the limit repose angle, it is determined that the vehicle body is in the dangerous region.